The Bureau of Legal Affairs hears and decides opposition to the application for registration of marks; cancellation of trademarks; cancellation of patents, utility models, and industrial designs; and petitions for compulsory licensing of patents. It also exercises original jurisdiction in administrative complaints for violations of laws involving intellectual property rights: provided, that its jurisdiction is limited to complaints where the total damages claimed are not less than Two hundred thousand pesos (Php 200,000).

The Director of the Bureau of Legal Affairs has the power to hold and punish for contempt all those who disregard orders or writs issued in the course of the proceedings. The Director has also the power to impose administrative penalties.